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083
FXUS62 KCAE 200920
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
520 AM EDT Thu Jun 20 2024

.SYNOPSIS...
High pressure along with dry weather and near normal
temperatures are expected through today. Unsettled conditions
are possible tomorrow and into the weekend as moisture moves in
from the Atlantic. Well above normal temperatures are expected
by Sunday into early next week.

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.NEAR TERM /THROUGH TONIGHT/...
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There is little change in the overall large scale pattern today as
upper ridging and high pressure continue to dominate the
weather. Expect another day of warm and dry weather conditions
as PWATs struggle to exceed 1 inch. Scattered cumulus are likely
to develop later today along with periodically gusty winds out
of the east. Any cumulus should dissipate quickly with the loss
of daytime heating, giving way to mainly clear skies tonight.
Clouds may increase towards daybreak as an area of low pressure,
Invest 92L, approaches the Georgia and Florida coasts but rain
is not expected until after daybreak. Temperatures will be
similar to previous days with highs around 90 degrees and lows
in the mid to upper 60s.
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.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
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An area of low pressure east of the Bahamas, Invest 92L, is
expected to move south of the region Friday. The NHC Tropical
Weather Outlook gives it a low (30%) chance for further
development in the next 48 hours. The expectation is that this
disturbance will remain disorganized, but infuse more moisture
into the region to support a chance of showers and thunderstorms
on Friday afternoon, mainly south of the I- 20 corridor. The
moisture increase will be significant, with PW values exceeding
1.5" and approaching 1.8" by late Friday afternoon across the
Southeast Midlands and CSRA. Additionally, temperatures will be
warmer than Thursday by a few degrees, with highs in the low to
mid 90s as a potent upper ridge and broad surface high pressure
situate over the TN Valley. The increased moisture will also
lead to more cloud cover and warmer overnight lows, mainly in
the upper 60s to around 70.

A warming trend really kicks into gear on Saturday, with highs
reaching the middle 90s to perhaps the upper 90s for a few
locations. Changes in the wind field, with more southerly flow in
the lower levels, will reinforce moisture availability and dewpoints
are expected to creep into the upper 60s to low 70s possible across
the southeast Midlands. However, this will be countered by northerly
flow aloft, as a mid and upper level low sets up off the coast of
NC. With PW values around 1.5"-1.7", daytime heating should
trigger isolated diurnally-driven convection across the area.
Storms should wind down with sunset, and overnight lows will be
mild again, only in the low 70s.
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.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
The main story in the extended forecast remains the heat. While
moisture will remain intact across the area with PW around 100-120%
of normal, its effect on apparent temperatures will be more
impactful than the increased risk for showers and thunderstorms.

Upper ridging will build across the southern tier of the CONUS and
remain in control into early next week. GEFS mean 850mb temperatures
are forecast to be 18-22C through the middle of next week, giving us
temperatures of 8-12 degrees above normal at the surface. There has
been little change in the overall high temperature forecast from the
NBM or the spread through at least Monday, though it should be noted
that the deterministic NBM highs on Monday seem to be at the 25th
percentile. The spread on Tuesday is wider, likely due to the
uncertainty regarding any convection which may interfere with peak
heating potential. Potent low level moisture (dew points in the
upper 60s and low 70s) is thought to yield max heat indices of 98F-
103F across the region, especially for Sunday through Tuesday. Its
also worth mentioning warm overnight lows, in the low to mid 70s.

There remains uncertainty for Tuesday and Wednesday as the pattern
shifts with a couple of disturbances moving through the region.
Ensemble PW means differ between the GEFS and the ECENS, with
the EC quite a bit drier than the consistently wet GEFS. Didn`t
deviate from the blend at this juncture since there is too much
uncertainty. Overall though, it does look like we`ll be entering
into a more active and summer-like pattern at temperatures
remain well above normal.

More information on the potential for moderate to major heat risk
late in the forecast period can be found at
wpc.ncep.noaa.gov/heatrisk.

&&

.AVIATION /09Z THURSDAY THROUGH MONDAY/...
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VFR conditions continue at the terminals early this morning with
just a few passing clouds. Light easterly winds should increase
after daybreak and may be gusty at times, especially this
afternoon. Dry conditions are likely to continue at all
terminals with scattered cumulus developing this afternoon and
dissipating after sunset. Winds should gradually diminish
tonight under clear skies though cloudiness may begin to
approach the terminals from the east towards the end of the
current TAF period.

EXTENDED AVIATION OUTLOOK...Brief restrictions possible in
isolated to scattered afternoon and evening thunderstorms Friday
through Sunday.
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&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...None.
GA...None.

&&

$$